try_v2 0.4.0

Provides a derive macro for `Try` ([try_trait_v2](https://rust-lang.github.io/rfcs/3058-try-trait-v2.html))
Documentation
warning: it is recommended to annotate try-types as `#[must_use]`
  --> tests/compilation/fail_MustUse.rs:8:1
   |
 8 | / enum ExitE<E> {
 9 | |     Ok(E),
10 | |     TestsFailed,
11 | |     OtherError(String),
12 | | }
   | |_^
   |
note: this warning originates from the macro invocation here
  --> tests/compilation/fail_MustUse.rs:7:17
   |
 7 | #[derive(Debug, Try, Try_ConvertResult)]
   |                 ^^^
   = note: this warning originates in the derive macro `Try` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0425]: cannot find value `fail` in this scope
  --> tests/compilation/fail_MustUse.rs:15:5
   |
15 |     fail
   |     ^^^^ not found in this scope